1. Field of the Invention
The present invention relates to a close-range photographing and general-range photographing method of a digital camera, and more particularly, to a method for close-range and general-range photographing in automatic light emission mode and manual light emission mode of a digital camera capable of photographing an object in close range by using embedded normal and macro flashes.
2. Description of the Related Art
Macro photography is photographing an object in a close distance equal to or less than 30 cm. In a film camera, a macro lens should be attached for macro photographing. However, in a digital camera, because the focal length is usually shorter than that of a normal film camera, it is possible to photograph an object in close range without a change of lens.
When macro photography is executed by a digital camera, the amount of light falls short of a required light amount for photographing an object because the distance between the digital camera and the object is short.
The conventional macro flash disclosed in the U.S. Pat. No. 4,816,854 to solve this problem as shown in FIG. 1. The macro flash 2 as shown has a ring shape separate from the main body of a camera so that the macro flash 2 can be coupled with the camera in contact with the outer circumference surface of a lens. The ring-shaped macro flash 2 is connected through a connector 9 to a control unit 5 controlling the macro flash 2 and at the same time having a function of a normal flash 6. The control unit 5 has a coupling unit 7 so that the control unit 5 can be connected to a flash synchronization apparatus, such as a hot shoe, disposed on the main body of the camera. According to this, the ring macro flash 2 operates in synchronization with a shutter button (not shown) and the amount of light is adjusted by a light emission sensor or other methods.
However, since the conventional technology disclosed in U.S. Pat. No. 4,816,854 needs separate apparatuses for macro photography, such as the ring macro flash, the control unit, and the hot shoe, it is not appropriate for use in a slim-type digital camera, and there is inconvenience in that the apparatuses for macro photographing need to be carried separately. Since a strobe light source for normal photographing is used concurrently, the amount of light required for macro photographing cannot be emitted uniformly, and the amount of light emission also cannot be controlled precisely.
In addition, a Xenon lamp type strobe light source, which is usually used for normal photographing, can emit light only when the minimum light emission condition is 10 μs or over. However, when photographing is performed 10 μs or over with the Xenon lamp light source, there is a problem in that the amount of light of an object is saturated. In particular, because it is desirable that photographing is performed within 1/30 second to prevent hand trembling when macro photographing is performed, it is inappropriate to use the strobe light source as a flash for macro photographing.
FIG. 2 shows a digital camera 10 and a visible ray irradiation means 22 for macro photographing, employed by the camera disclosed in Japanese Laid-Open Patent Application H8-82738. The digital camera 10 has a lens 14, a light reception window 15, a shutter button 18, and a finder optical system 16. The visible ray irradiation means 22 formed separately from this digital camera has a pair of light sources 24, such as LEDs and Xenon, and is formed to be fixed to the lens 14 formed on the main body 12 of the camera.
The optical axis 14A of the lens 14 and the two optical axes 24A of the two light sources 24, which are disposed on the visible ray irradiation means 22, cross at a point that coincides with a close-up position. Thus, even when the optical axis 16A of the finder optical system 16 does not coincide with the close-up position on the lens optical axis 14A, whether or not the finder optical system optical axes 16A is at the center of a photographing screen can be determined by whether or not the optical axis 14A of the lens 14 coincides with the optical axes 24A of the two visible rays. However, in this conventional technology there is also a problem in that, for macro photographing, a separate visible ray irradiation means is required.
Besides the above disclosures, Japanese Laid-Open Patent Application Nos. 2003-262900 and 2002-099042 disclose apparatuses for macro photographing, but these all require separate visible ray irradiation means for macro photographing.